Bioresearches showcase Adaptive Management approach.

Bioresearches Group marine ecologist, Dr Jacqui Bell recently joined delegates from across Australasia at the Coasts & Ports Conference, held in Auckland. Jacqui presented findings from the construction phase monitoring, carried out within the marine environment surrounding NZ Transport Agency’s State Highway 16 Causeway Upgrade Project, in Auckland.

The Causeway Project has involved raising and widening 4.8km of nationally significant coastal roading infrastructure to increase vehicle capacity and to mitigate coastal flooding, particularly as sea levels continue to rise. It runs adjacent to the Motu Manawa - Pollen Island Marine Reserve and extensive monitoring of impacts on the marine environment is a resource consent requirement.

To date, monitoring has not detected any significant changes over time. It has, however, provided a better understanding of the local marine environment. Results have indicated that at the exposed sandy sites north of the causeway, species abundance is in general low and diversity is relatively high, likely due to the increased level of predation and competition, and the good sediment quality at these sites. Conversely, the muddy mangrove sites located along the urban fringes are dominated by a few highly abundant, very hardy species. These sites have background contaminant levels, not associated with the construction activity. They are highly exposed to stormwater runoff, which is the main contributing factor reducing the quality of these habitats.

The paper concludes by proposing an adaptive management approach to the ecological monitoring for this project, in order to focus more on the ecologically important areas adjacent to the project and less on the sites already affected by the neighbouring urban environment. An adaptive management regime has since been approved by Auckland Council and The Department of Conservation. This has been a great outcome for all involved, as it has reduced cost to the client, whilst continuing to allow the management of risk by retaining statistical power for detecting ongoing environmental changes. Bioresearches Group hopes that this will be one of the first examples of how an adaptive management approach to ecological monitoring can be implemented successfully in New Zealand.